Data represents a significant asset for many entities. Consequently, securing stored data against theft and/or data loss, whether accidental or caused by malicious activity is enormously important. Failure to do so can be costly in terms of wasted manpower, loss of goodwill from customers, loss of time and/or potential legal liability. To ensure proper protection of data for business and legal purposes, many entities back up data to a physical storage media such as magnetic tapes or optical disks. Traditionally, backup would occur at each machine controlled by an entity. As the sophistication of network technology increased, many entities turned to enterprise level backup in which data from multiple machines on a network is backed up to a remote library. Typically, a library includes a variety of components which include a plurality of media for data storage such as, for example, multiple magnetic tapes. Centralized data backup has the advantage of increased volume, efficiency and redundancy.
In many systems, the data to be backed up and backup commands are sent over a network from multiple machines on the network to a library. One example of a library commonly used in enterprise backup systems is a magnetic tape library. A magnetic tape library can comprise components such as tape cartridges (containing magnetic tape), robots, tape slots and tape drives. A typical magnetic tape library contains multiple cartridge slots in which tape cartridges can be stored. Tape cartridges, commonly referred to as tapes, are physically moved between cartridge slots and tape drives by a robot. The robot is controlled by commands received from the host devices on the network. When specific data is required, a host device determines which cartridge slot contains the tape cartridge that holds the desired data. The host device then transmits a move-element command to the robot and the robot moves the tape cartridge to a tape drive which reads the desired data from the tape cartridge.
In a SCSI tape library, devices that are part of the library are typically addressed by target number. Thus, each drive and robot of a tape library typically has a target number. Cartridge slots, on the other hand, are addressed by element numbers that are used by the robot to locate the slots. Because the robot also places tape cartridges in the drives, each drive is also associated with an element number.
Libraries can contain private or sensitive data. Consequently, it may be desired to keep data confidential and prevent unauthorized persons or machines from accessing data stored in a library. For example, because cartridges are portable and may be removed from a tape library, it may be desirable to prevent data in a library from being accessed by unauthorized users or machines in the event tape cartridges are stolen or inappropriately accessed over a network by an unauthorized user. To this end, data to be stored in a library may be encrypted to prevent unauthorized users or machines from accessing the data.